Correlation of MRI enhancement features and histopathology after partial resection of nomal brain:an experimental study in rats / 实用放射学杂志

ABSTRACT

Objective To study the contrast enhanced magnetic resonance imaging (MRI)features of surgical margin and its path-ologic basis of the experimental rat model by resecting partial brain tissue.Methods Forty-two rats were randomly divided into six experimental groups (postoperative 1d,3d,7d,14d,21d,28d groups)and one contrast group.A partial resection of the parietooc-cipital region was performed.MRI procedures consisted of T1 WI and T2 WI and contrast enhanced T1 WI,pre-and postcontrast scan-ning were enforced in different postoperative days.Brain tissue samples were obtained after MRI examination.Pathological study was made and the results were compared with MRI findings.Results (1 )The earliest enhancement was observed around surgical margin on the first day after surgery,which enhancement was lasted until 28 days;(2)The enhancement of the surgical margin was significantly increased after 7d,the signal intensity ratio in this period reached the peak,but this ratio between 7d and 14d had no ob-vious disparation.The degree of enhancement gradually weakened in the next few days;(3)The number of neovessels reached the peak at 7d,which was higher than that at other experimental groups and contrast group (P 0.05).Conclusion The contrast enhanced MRI features of the surgical margins after resected partial brain tissue is related to the time of the postoperation,and the neovascularization plays an importent role in this process.